Carbon Footprint

First of all, I'd like to thank everyone on this board, for all of their insight and information that they share for guys like me to try and figure out our problems and share solutions! Ok so I bought a 2003 996tt with 47K tiptronic in the most unusual of circumstances. I bought the car with the engine out at auction (I know risky to say the least) but the price was right so I jumped on it. I managed to find out the history of the car and why the engine was out, it was taken to a local pcar dealer (by a used car dealer who bought it at auction) complaining of excessive smoking and knocking....dealer borescoped all cylinders, saw nothing obvious and advised tearing down engine. Customer declined and somehow it ended up at another auction in 2 pieces.
Once I acquired the car, I took the engine to local indy and asked them to do as many tests as possible on engine since it was already out of the car. They were busy, had the engine for 2 weeks and only did a leak down test... 1% on 1-5 and 4% on number 6. Number 6 was also oil fouled and there was oil in intake tracts. They then advised me that we should put engine back in car and do further tests from there ( I really wanted them to pull the valve covers and check for signs of a stuck lifter as it seemed like the logical explanation of a knock) So I took the engine back home and installed it, changed the oil (saw nothing funny but I don't know if the previous dealer changed the oil or not) put in new plugs, got everything hooked up and it would crank and crank and not fire.
Thanks to all of the forum info I figured it was a bad crank position sensor and it was. So it starts up puking oil smoke like no other..... I mean you would have thought there was a grass fire around! I read that it takes 8-8.5 qts to fill with filter, and it took 9.5 to get level on dash to one mark under full.
So this has me thinking that the electronic dipstick is not reading right and it has consistently been overfilled with oil, thus all of the smoking. It definitely had a good knocking sound very consistent with rpm increase and decrease, never changing at all. I ran the engine a total of probably 2 hours in 15 -20 min sessions, and drove the car 12 miles never going above 3500 rpm. I drained some oil, sent a sample to Blackstone (awaiting results) and cut open the filter to find not a speck of metal. My son and I used a microphone and the computer to time the speed of the knock, and at 850- 900rpm it was 6.5-7 knocks per second....seems to say valvetrain not bottom end because bottom end would have been 14-15 knocks per second right?
Take car back to same indy who initially thought I had a ring starting to let loose or something else in the bottom end, he listened with a stethoscope and says it cyl no. 3 probably stuck lifter. Then he hooks up his diagnostics and sees that number 2 is running slightly rough (1.3) and all other cylinders reading 0.0. Great News! I need lifters not a new engine. He quotes me 22 hours labor @ $125/, and $1300 for lifters (only one bank!) seems a little steep when everyone else on here seems to be paying around $4,000 for all of the lifters on both sides. Same indy says he has never opened up a turbo, and he is one of the biggest porsche shops in denver been around for decades.
I am not afraid to tear it open and do them myself, just a little nervous about the whole timing the cams thing, and the tools I would need. Anyone in Denver ever done this and have the tools and want to make some side cash helping me? Or can anyone lead me to the best source for the tools, and instructions on timing? Took the car out tonight and actually ran it..... on the gas up to 5500 rpm to see if it would clear up...OMG this thing is fast, can't wait to get it fixed and start enjoying it!

Thanks in advance for all your help

Kevin

Wow this is a strong first post.. Welcome.. I have a few recommendations for shops in Denver.

PM me for a few names..

What dealer are you using? You mentioned that you are buying parts from a local dealer? Which dealer did the original diagnostics?

Macster

For my 2003 Turbo with the engine up to temp and a 20 minute drain interval it takes 7.8l of oil to have the oil level at the max line - not above or below it. The level is confirmed after starting the engine and letting it idle until the fresh oil has come up to temperature, which when the oil is drained hot doesn't take much time.

The 7.8l includes the oil needed to make up what is lost with the filter change, too.

If you are putting in 9.5 quarts of oil that's 8.9 liters of oil and that's too much oil unless you are letting the oil drain say overnight. There is a refill amount call out for an overnight drain but I do not know what it is though almost certainly it is more than the amount required for a 20 minute drain interval.

While it may seem the wrong way 'round you put in a specific amount of oil and thus confirm the digital oil level system is working properly by the fact it reports the oil level at what the factory manual says it should be.

For the knocking noise at say 800 RPMs the intake/exhaust valves open every other revolution. Thus the intake/exhaust valves open 400 times per minute or every 150mS or approx. 6.6 times per second.

Thus the noise could be a bad lifter or a broken valve spring, to list a couple of possible explanations.

However, with no misfires I wonder how bad can the problem be?

This is not to say the noise can be ignored. Not at all. The source of the noise needs to be clearly ID'd and addressed.

I would not take the car to an indy that has never had a Turbo engine apart. You want a shop that has been inside these engines often and successfully I might add.

rmc1148

Best advice is to talk to Kevin= he knows what he's talking about. I do not know why you would undertake a project like this without extensive knowledge of the motor= but that's a whole other conversation. Good luck.

Carbon Footprint

Kevin, Thanks I will send you a pm.
Macster, That is exactly what I was trying to say thanks for confirming.
rmc1148, It's not like I've never built a motor before..... I built 700hp supercharged engines for my 38' offshore boat, and usually work on everything myself. Just did a head gasket on my duaghter's land rover..... I have not torn apart a 996tt engine, but that doesn't mean I can't. Thanks for the concern though. I would have thought that by reading my post through and through, one could tell that I have some common sense when it comes to cars.

Ck986

Please keep us updated and good luck. I love reading about these types of projects.

Carbon Footprint

Will do! Next step is to source the tools I will need, pull the engine back out, and open up the top ends for inspection. Probably get started on it next week.

cbracerx

Good luck! I've seen the timing done with the factory special tools and with dial indicators and fixtures. Both ways work. Keep us informed of your progress.

rmc1148

https://rennlist.com/forums/996-turb...ing-tools.html Timing thread.

32krazy!

understanding the way this motor is put together is key. download the service manual from 6so and read how to tear the motor down. common mistake is missing the small bolt that holds the thrust cap onto the cams. when "porsche" techs who have never worked on these motors can't get the cap off they start prying on the cap usually breaking it. the caps and cam housing is a matched set. 2000$ to replace. also a full set of lifters for both banks costs about 2200$. replace them with 997 turbo lifters. heavier springs different design more improved

the tools needed to properly tear down and rebuild and time the cams cost in excess of 5000$. if your going to do this a bunch ok if not its not worth the cost to do it yourself.

rmc1148

^This is the kind of thing I was talking about and did not mean to sound rude. These motors are complicated and can be quite expensive to repair especially if you make mistakes along the way. Good post Krazy.

Carbon Footprint

Thanks for the heads up guys, I realize the tools are expensive, but have seen several alternatives for timing tools sold by others for a fraction of the cost? I did download the 996tt manual (the one from northcarolinainvestor) but haven't scoured the section on engine disassembly yet.
Does anyone have any experience with the other tools like stomski, baum, sam stag, or others?

32krazy!

you aren't to far from las vegas. silly rabbit motorsport can open it up and fix whatever you need for a reasonable price. worth a call to sean and talk about it

Carbon Footprint

So against my better judgement, I've been driving her around the neighborhood a little bit, partially trying to see if my supposed stuck lifter clears up and partially because I'm just too impatient to wait! What a fun car, makes my old '74 911 targa seem like it was a moped lol.
So I have this smoking issue that I am pretty sure is related to someone overfilling it with oil and getting it everywhere in the system........doesn't smoke a lick at startup, only after fully warmed up and driving it a while. Then if I let it sit for a while and start it back up, no more smoke til warm.
Someone mentioned the overfill could have gotten oil in the exhaust that will take a while to burn off? Any thoughts? Leakdown is 1% and cylinder walls are clean.
How long does it take to clear out oil from an overfill??

Macster

No experience from any engine oil overfill but my Boxster's gone through several AOS's and these when they fail route a lot of oil to the engine. Enough oil that the running engine will fill the air with oil smoke. In one case the engine even suffered a fortunately mild hydraulic lock from too much oil in the cylinders.

The service manager told me it can take some driving to work all the oil out of the intake and exhaust. I seem to remember he quoting 50 miles.

After two other failures I think this number inflated. After the 2nd one was replaced I just drove the thing around town a bit to make sure the car was running ok and then drove around 90 miles.

I don't recall the thing smoking any at all at any time.

After the 3rd failure I drove the car around town enough to make sure it was running right and there was no smoking.

I would hazard a guess that if the oil level is correct the smoking is not from the overfill but possibly from turbo seals.

But before you worry about the seals, there can be a problem with the Turbo that if oil gets into the intake it will of course being liquid end up in the lowest places of the intake system and these are the intercoolers.

So you might want to remove the hose on the lowest end of the intercooler then let the car sit with the hose disconnected and let any oil drain from the hoses and intercoolers before you connect the hoses again.

If oil drains well you know.

If no oil drains then if the smoking persists you might remove the hoses enough to check the turbo compression wheel. My info is is if the thing is wet with oil this can be a sign the turbo seal is leaking.